1. In this combustion system, coal is put into the coal hopper and then taken to the coal bunker using a conveyor.
2. From the coal bunker, coal is pushed into the combustion chamber using a screw feeder. The amount of fuel that enters is regulated by a motor that has been set to rotate by the manufacturer.
3. The fuel pushed by the screw feeder falls on the chain grate stoker.
4. As the chain grate rotates along the furnace, the coal burns before falling at the end of the chain as ash.
5. Accurate settings and calculations are required to determine the rotation of the chain grate motor, air damper and baffles to provide good performance so that combustion is perfect and produces as little unburned carbon in the ash as possible.
Advantages of using a chain grate stoker:
1. Does not require a large space.
2. Does not require a lot of electrical power because the motors used are small.
3. Investment costs are not too expensive when compared to the Fluidized combustion system.
Chain Grate Weaknesses:
1. Operation is quite difficult because it requires precise calculations to set the rotation of the chain grate motor, air damper and baffles so that the coal burns out exactly at the end of the chain.
2. Susceptible to damage because the moving parts are in places with very high temperatures.
3. Requires regular maintenance because a lot of soot from combustion sticks to the boiler components.
4. Requires coal with at least 7% ash content to coat the chain.
5. Must use high calorie coal.
6. The size of the coal must be uniform.